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Biomedical subjects

M J Harrison

Publications and source records attributed to M J Harrison.

At least 73 records · Page 4Linked to original sources
PubMed1998

Middle cerebral artery occlusion in the rat: consistent protocol for a model of stroke.

Variability in the effects of the intraluminal suture method of middle cerebral artery occlusion (MCAO) in the rat has been a common and disadvantageous finding. Therefore, we systematically investigated the effects of suture type and rat strain on outcome. First, the clinical and neuropathological effects of permanent MCAO with either an uncoated or a silicone-coated nylon suture were studied over 7 days in Sprague-Dawley rats (n = 36 for each type of suture). Outcome was less severe with the uncoated compared with the silicone-coated suture (e.g. total cerebral infarct volume at 24 h before any fatalities was 119.9 +/- 79.8 mm3, cf. 183.0 +/- 36.5 mm3, n = 12 for each, P < 0.05; and overall mortality rate was 12.5% cf. 33%, respectively), but much more variable (coefficient of variation was 66.6% cf. 19.9%, respectively). Second, being more consistent in its effects, the silicone-coated suture was further studied in Wistar and Fischer-344 rats (n = 12 for each). Seventy-five per cent of the Wistar's died prematurely from gross hemispheric oedema. Motor deficit and extent of infarction in the Fischer-344 rats were both significantly greater compared with Sprague-Dawley rats (e.g. total cerebral infarct volume at 24 h in the former was 253.6 +/- 25.4 mm3, n = 11, P < 0.05), and more consistent (coefficient of variation was only 10.0%). It was concluded that the silicone-coated suture and the Fischer-344 rats strain produced the most consistent results and their novel combination provides a reliable acute stroke model.

Animals↗
PubMed1998

Cloning and characterization of two phosphate transporters from Medicago truncatula roots: regulation in response to phosphate and to colonization by arbuscular mycorrhizal (AM) fungi.

Most vascular plants can acquire phosphate from the environment either directly, via the roots, or indirectly, via a fungal symbiont that invades the cortical cells of the root. Here we have identified two cDNA clones (MtPT1 and MtPT2) encoding phosphate transporters from a mycorrhizal root cDNA library (Medicago truncatula/Glomus versiforme). The cDNAs represent M. truncatula genes and the encoded proteins share identity with high-affinity phosphate transporters from Arabidopsis, potato, yeast, Neurospora crassa, and an arbuscular mycorrhizal (AM) fungus, G. versiforme. The function of the protein encoded by MtPT1 was confirmed by complementation of a yeast phosphate transport mutant (pho84). The K(m) of the MtPT1 transporter in this system is 192 microM. MtPT1 and MtPT2 transcripts are present in roots and transcript levels increase in response to phosphate starvation. MtPT transcripts were not detected in leaves. Following colonization of the roots by the AM fungus G. versiforme, both MtPT1 and MtPT2 transcript levels decrease significantly. Down-regulation of phosphate starvation-inducible genes in mycorrhizal roots appears to be a common occurrence and a homologue of a phosphate starvation-inducible purple acid phosphatase is also down-regulated in the mycorrhizal roots. The functional characteristics and expression patterns of the MtPT transporters are consistent with a role in the acquisition of phosphate from the environment but suggest that they may not be involved in phosphate uptake at the symbiotic interface in mycorrhizal roots.

Amino Acid Sequence↗
PubMed1998

Impact of marital quality and parent-infant interaction on preschool behavior problems.

This study examined the relationships between parent interactions with healthy term and preterm infants at 12 months of age, marital quality, family socioeconomic status, and preschool behavior problems. Eighty mothers and 74 fathers were observed in the home during an interaction with their child (Nursing Child Assessment Teaching Scale), and this group of parents completed the Dyadic Adjustment Scale questionnaire (marital quality) 12 months after the child was discharged from the hospital. Each parent completed the Eyberg Child Behavior Inventory when their child was four years of age. The parent and infant interaction scores were not predictive of later child behavior problems. Maternal perceptions of marital quality at 12 months predicted the frequency (Eyberg Intensity score) and impact (Eyberg Problem score) of the child's problematic behaviors reported by mothers. Marital quality and family socioeconomic status predicted the impact of behavior problems for fathers. There were no significant differences between preterm and term children or between boys and girls in the frequency or impact of problematic behaviors. Mothers reported a significantly greater frequency of behavior problems than fathers of the same children. The implications of these findings for nurses who work with families and young children are discussed.

Adult↗
PubMed1998

Nursing research on the health of low-income women.

The purpose of this paper is to describe the scope of published nursing research on the health of low-income women. Williams' (1990) model of the relationship between socioeconomic status and health was used as a framework for the analysis. This model includes three major components: Medical Care, Psychosocial Factors, and Health Outcomes. There is a body of published nursing research that addresses a range of health issues of low-income women. Our search of English language literature published between 1989 and 1995 retrieved 49 articles that met the inclusion criteria. Most of the nursing studies examined a portion of Williams' model but did not address multiple components. The most frequently addressed component was Psychosocial Factors, particularly health practices, stress and coping, and social ties. Williams' model was an effective framework to classify nursing research. Results of our analysis suggest that further research is needed on the pathways by which low income influences health and on the effectiveness of nursing interventions.

Adolescent↗
PubMed1998

Detection of Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus DNA in CSF from persons infected with HIV who had neurological disease.

OBJECTIVES: To determine the frequency and clinical relevance of Epstein-Barr virus (EBV) and Kaposi's sarcoma associated herpesvirus (KSHV) DNA detection in the CSF from patients infected with HIV. METHODS: Cerebrospinal fluid was obtained prospectively from 115 consecutive patients infected with HIV undergoing diagnostic lumbar puncture for investigation of neurological disease. Amplification of DNA was performed using a nested polymerase chain reaction (PCR) for detection of EBV internal repeat and KSHV minor capsid sequences. RESULTS: EBV DNA was detected in the CSF supernatant of 18 patients. This included all patients with primary CNS lymphoma (seven patients) or a combination of systemic and CNS lymphoma (two patients). By contrast EBV DNA was not detected in the CSF supernatant of any patient with systemic, but not CNS, lymphoma (10 patients). EBV DNA was also detected in the supernatant of nine further patients without a diagnosis of lymphoma at the time of lumbar puncture, two of whom subsequently developed CNS lymphoma. No EBV DNA was detected in CSF supernatant from the remaining 87 samples (two of these patients subsequently developed lymphoma). KSHV DNA was detected in the CSF of two patients, one had systemic (but not CNS) lymphoma and the other did not have lymphoma. CONCLUSION: A diagnosis of CNS lymphoma is strongly associated with the presence of EBV DNA in CSF. In the absence of clinical and radiological features of CNS lymphoma, the presence of detectable CSF EBV DNA may predict subsequent tumour development. KSHV DNA is rarely detected in CSF in this patient group and shows no correlation with lymphoma or other neurological disease.

AIDS Dementia Complex↗
PubMed1998

Evidence of CNS impairment in HIV infection: clinical, neuropsychological, EEG, and MRI/MRS study.

OBJECTIVES: To identify by clinical examination, EEG, MRI, and proton spectroscopy, and neuropsychological assessment the prevalence of signs of CNS involvement in patients infected with HIV, and to relate such findings to the evidence of immunosuppression. METHODS: The design was a cross sectional analysis of a cohort of male patients with infected HIV with an AIDS defining diagnosis or low CD4 count (<350), and seropositive asymptomatic subjects, both groups being followed up in a longitudinal study. Control groups consisted of seronegative subjects from the same genitourinary medicine clinics. RESULTS: This report sets out the cross sectional findings at the seventh visit in the longitudinal study. Patients with AIDS had more signs of neurological dysfunction, poorer performance on a neuropsychological test battery, were more likely to have an abnormal EEG, and to have abnormalities on MRI. They more often had cerebral atrophy, abnormal appearing white matter, and abnormal relaxometry and spectroscopy. There was little evidence of abnormality in seropositive people who had a CD4 count >350 compared with seronegative people from a similar background. CONCLUSIONS: Detailed testing failed to disclose significant CNS impairment without immunosuppression in men infected with HIV. Findings from MRI and magnetic resonance spectroscopy (MRS) correlated with those of the neurological examination and neuropsychological assessment. A combination of such assessments offers a simple surrogate for studies of CNS involvement in HIV disease.

AIDS Dementia Complex↗
PubMed1998

Magnetic resonance imaging, thallium-201 SPET scanning, and laboratory analyses for discrimination of cerebral lymphoma and toxoplasmosis in AIDS.

OBJECTIVES: To compare the results of magnetic resonance imaging (MRI) and thallium-201 (201Tl) SPET scanning with laboratory analyses including CSF DNA detection, brain biopsy, and necropsy in the discrimination of cerebral lymphoma and toxoplasmosis in patients with AIDS. METHODS: A retrospective study of 32 patients infected with HIV who had focal CNS lesions on MRI as a result of either lymphoma or toxoplasmosis. RESULTS: 18 patients had lymphoma, 12 had toxoplasmosis, and two had both. Toxoplasma IgG antibodies were detected in only seven patients--four with toxoplasmosis, two with lymphoma, and one with both diagnoses. Epstein-Barr virus DNA was detected in CSF of all six patients with lymphoma and none of two with toxoplasmosis. MRI showed multiple lesions in 23 patients, appearances did not discriminate between lymphoma and toxoplasmosis; nine patients had single lesions, of these eight had lymphoma (p = 0.044, two tailed Fisher's exact test) 201Tl SPET showed accumulation in 17 with lymphoma and six with toxoplasmosis (p = 0.034, two tailed Fisher's exact test). Of nine patients with single lesions on MRI and 201Tl SPET with focal accumulation eight had lymphoma. 201Tl SPET uptake ratios of > or = 2.9 were only seen with lymphoma. CONCLUSION: Knowledge of patients' toxoplasma serostatus does not aid discrimination between lymphoma and toxoplasmosis. Single lesions on MRI with focal accumulation of 201Tl strongly suggest lymphoma. Multiple lesions on MRI with 201Tl SPET uptake ratios > or = 2.9 also suggest lymphoma; uptake ratios less than 2.1 do not aid discrimination. Detection of Epstein-Barr virus DNA in CSF is highly sensitive and specific for cerebral lymphoma.

AIDS-Related Opportunistic Infections↗
PubMed1998

Neuroprotection of the brain during cardiopulmonary bypass: a randomized trial of remacemide during coronary artery bypass in 171 patients.

BACKGROUND AND PURPOSE: Neuropsychological impairment may follow coronary artery bypass surgery as a result of peroperative cerebral microembolism. The hypothesis that remacemide, an NMDA receptor antagonist, would provide protection against such ischemic damage has been tested in a randomized trial. METHODS: One hundred seventy-one patients undergoing coronary artery bypass surgery by a single cardiothoracic surgical team were randomized to receive remacemide (up to 150 mg every 6 hours) or placebo from 4 days before to 5 days after their bypass procedure. Peroperative monitoring included an estimate of the number of microembolic events detected by transcranial Doppler ultrasonography of the middle cerebral artery. A battery of 9 neuropsychological tests was administered before and 8 weeks after surgery. RESULTS: The proportion of patients showing a decline in performance of 1 SD or more in 2 or more tests was reduced in the treated group (9% versus 12%), but this was not statistically significant. On the other hand, overall postoperative change (reflecting learning ability in addition to reduced deficits) was more favorable in the remacemide group, which demonstrated significantly greater improvement in a global z score (P=0.028) and changes in 3 individual tests (P<0.05). The 2 patient groups were well matched, including for the burden of microembolic events. CONCLUSIONS: This is the first study to show statistically significant drug-based neuroprotection during cardiac surgery. In addition to offering improvement in cerebral outcome for such at-risk patients, it supports the hypothesis that drugs acting on the excitotoxic mechanism of ischemic cerebral damage can be effective in humans.

Acetamides↗
PubMed1998

Short echo-time proton magnetic resonance spectroscopy in regions of severe HIV-related diffuse white matter abnormality on MRI.

The purpose of this study was to determine whether short echo-time proton magnetic resonance spectroscopy (H-MRS) could detect mobile lipid resonances attributable to myelin breakdown products in the deep cerebral white matter of patients with AIDS who have severe diffuse/patchy white matter hyperintensity on T2-weighted magnetic resonance imaging (MRI). Seven patients with AIDS and clinical HIV-associated dementia complex (HADC) and 12 male controls were studied at 1.5T using a single 8 ml voxel, gradient localised, stimulated echo acquisition mode (STEAM) spectroscopy sequence. Spectra were acquired at an echo time of 20 ms with a repetition time of 5000 ms. No spectroscopic peaks were identified at 0.9 ppm and 1.3 ppm (corresponding to lipid resonances) in 6 of the 7 patients with AIDS or in any of the controls. Lipid resonances were identified in 1 patient who had been taking anti-retroviral therapy for 8 weeks. Follow up MRI/H-MRS, performed after a further 14 weeks of anti-retroviral therapy, showed partial resolution of white matter hyperintensity and lipid resonances were not detectable. These data suggest that mobile lipids are only rarely detected by H-MRS in patients with HADC and abnormalities on MRI and that their presence may be transitory.

AIDS Arteritis, Central Nervous System↗
PubMed1997

The primate community of the Lopé Reserve, Gabon: diets, responses to fruit scarcity, and effects on biomass.

The diets of all diurnal primates (Gorilla g. gorilla, Pan t. troglodytes, Mandrillus sphinx, Colobus satanas, Cercocebus albigena, Cercopithecus nictitans, C. pogonias, C. cephus) in the Lópe Reserve, central Gabon, are described from qualitative and quantitative data collected over 10 years. A total of 397 foods were recorded, of which 91% were from plants. The diet of seven of the eight species were numerically dominated by fruit, the exception being Colobus satanas with a diet dominated by seeds. When proportion of feeding time was examined, fruit remained the dominant food class for six species, while Cercocebus albigena, like the black colobus, spent most time feeding on seeds. The number of foods recorded per species ranged from 46-220, but dietary breadth of the four species that have not been subjects of detailed study was certainly underestimated. Almost half of the foods (46%) were eaten by only one species, and only four (1%) were recorded for all eight species. At Lópe, fruit is scarce for 2-3 months during the annual dry season, and fruit crop failures can prolong this period of scarcity to as many as 8 months in some years. When fruit is scarce, the diets of all the species changed to include more nonfruit foods, but chimpanzees and the three species of guenons maintained a fruit dominated diet. The total biomass of the Lópe primate community is 374 kg/km2, which is low compared to other sites in tropical Africa. Within the Lópe community, biomass correlates negativity with degree of frugivory, suggesting that fruit availability may be critical, but this does not explain the low total biomass compared to other sites. Neither floristic diversity nor the composition of the primate community at Lópe can account for the biomass. While historical events such as climate-induced changes in forrest cover, disease, or impact of human activities cannot be ruled out, we conclude that the most likely explanation of low primate biomass is the occurrence of an ecological "catastrophe" in the fairly recent past from which populations have not yet recovered. We believe that the most likely scenario was climate-mediated disturbance of flowering of important fruit food species. Prolonged fruit scarcity would have caused mortalities and affected the most frugivorous species more severely.

Animals↗
PubMed1997

Magnetic resonance imaging of the brain and cerebral proton spectroscopy in patients with systemic lupus erythematosus.

OBJECTIVE: To investigate the prevalence and extent of cerebral changes in patients with systemic lupus erythematosus (SLE) by magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). METHODS: SLE patients (47 women) and controls (25 women) underwent 1.5T MRI. A semiautomated segmentation technique calculated cerebrospinal fluid (CSF) and brain volumes. Proton MRS of the frontal and parieto-occipital white matter yielded metabolite ratios of N-acetyl groups (NA), choline, and creatine. RESULTS: Compared with the control group, the SLE patients more often had cerebral atrophy on MRI (32% versus 0%), confirmed by an increase in the CSF to intracranial volume ratio. The patients also had old infarcts and hemorrhages (8.5% versus 0%) and more small white matter lesions (23% versus 8% had > 5 such lesions). MRS showed relative reduction of NA peaks. Although no patient was studied when acutely ill, prior neurologic involvement was related to abnormal findings. CONCLUSION: MRI and MRS are helpful in the investigation of cerebral complications of SLE. There are chronic changes which may be ischemic in nature. Their precise cause, consequences, and prevention are current challenges.

Adult↗
PubMed1997

High magnetic susceptibility coatings for visualisation of optical fibres on a specialised interventional MRI system.

The aim of this study was to develop methods of visualising optical fibres on MRI scans for monitoring interstitial laser therapy. Scans were performed on a specialised MRI extremity scanner at 0.17 T. Optical fibres of 0.4 mm diameter used for delivering laser energy were coated with iron particles from a superferromagnetic contrast agent. MR images of the fibres were acquired using gradient echo sequences (TR/TE = 300/10, 1 mm in-plane, 3 mm slice) and assessed for fibre visibility. Coated fibres could be resolved as lines 2 +/- 1 mm wide using the gradient echo sequence. Uncoated fibres were invisible on the sequences used for in vivo therapy monitoring due to partial volume averaging. It is concluded that optical fibre visualisation by MRI may be improved by coating with ferromagnetic particles. Biocompatibility requires further assessment, but direct coating appears to be a promising method for fibre visualisation in MR-guided laser therapy.

Contrast Media↗
PubMed1997

Cerebral volumes and spectroscopic proton metabolites on MR: is sex important?

One of the factors that may influence the selection of appropriate controls for MR studies of the brain is gender. This study compared calculated intracranial volumes and proton spectroscopic metabolite ratios obtained from male and female volunteers. Thirty-two males (mean age = 36; range = 30-53 yr) and 19 females (mean age = 39; range = 26-53 yr) underwent investigation at 1.5T. Brain, cerebrospinal fluid (CSF), and intracranial (ICV = brain + CSF) volumes were measured by the CLASS technique on data acquired using an axial dual spin-echo imaging sequence (TE = 20/90 ms, TR = 3500 ms). Proton spectra (TE = 135 ms, TR = 1600 ms) were acquired from an 8 ml cubic region placed in parieto-occipital white matter. The mean male and female brain, CSF and ICV were significantly different (p < .005). However, the mean CSF/ICV ratios of the two groups were not significantly different. The N-acetyl/choline and choline/creatine metabolite ratios of the two groups were significantly different (p < .05). When comparing proton metabolite ratios and absolute brain volumes between groups, gender is an important factor. CSF/ ICV ratios do not appear to depend on gender.

Adult↗
PubMed1997

The measurement of R2, R2* and R2' in HIV-infected patients using the prime sequence as a measure of brain iron deposition.

Brain iron deposition was assessed at 1.5 T in the caudate nucleus, globus pallidus and frontal and parieto-occipital white matter in 28 human immunodeficiency virus (HIV)-infected patients and 15 control subjects with a new Partially Refocussed Interleaved Multi-Echo sequence by measuring 1/T2, 1/T2* and 1/T2' (i.e., R2, R2* and R2'). There were significant differences in the R2 and R2* of the caudate nucleus (p < 0.0001 and p < 0.05) and the R2, R2* and R2' of the globus pallidus (p < 0.01, p < 0.005 and p < 0.05) in HIV-infected patients compared to control subjects. There was a trend for higher values of R2, R2* and R2' in the globus pallidus and caudate nucleus in HIV-infected patients with later stage HIV disease. These results suggest that there is greater iron deposition in the basal ganglia of HIV-infected patients compared with control subjects, with a predilection for the globus pallidus. The relationship between iron deposition in the brain and various parameters of severity of HIV infection remains uncertain.

AIDS Dementia Complex↗
PubMed1997

A novel gene whose expression in Medicago truncatula roots is suppressed in response to colonization by vesicular-arbuscular mycorrhizal (VAM) fungi and to phosphate nutrition.

A cDNA clone (Mt4) was isolated as a result of a differential screen to identify genes showing altered expression during the interaction between Medicago truncatula and the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus versiforme. Mt4 represents a M. truncatula mRNA that contains numerous short open reading frames, the two longest of which are predicted to encode polypeptides of 51 amino acids each. One of these open reading frames shares a short region of identity with a phosphate starvation-inducible gene from tomato. Mt4 gene expression is regulated in response to colonization by mycorrhizal fungi: transcripts were detected in non-colonized roots and levels decreased in both M. truncatula and M. sativa (alfalfa) roots after colonization by G. versiforme. Transcript levels also decreased during the incomplete interaction between G. versiforme and a M. sativa mycorrhizal minus (myc-) line, indicating that the down-regulation of this gene occurs early during the interaction between the fungus and its host plant. Phosphate levels in the nutrient media also affected the expression of the Mt4 gene: transcripts were present in the roots of plants grown under phosphate-deficient conditions, but were undetectable in the roots of plants grown under phosphate sufficient conditions. Furthermore, expression was only observed when plants were grown under nitrogen-sufficient conditions. Northern blot analyses indicate that Mt4 transcripts are present primarily in roots and barely detectable in stems or leaves. Thus, Mt4 represents a M. truncatula gene whose expression is regulated in response to both colonization by mycorrhizal fungi and to the phosphate status of the plant.

Amino Acid Sequence↗
PubMed1997

Cerebral proton magnetic resonance spectroscopy in asymptomatic HIV infection.

OBJECTIVE: To determine whether proton magnetic resonance spectroscopy (MRS) demonstrates central nervous system abnormalities in asymptomatic HIV-1-infected individuals. DESIGN: Both prospective and retrospective cross-sectional analyses of MRS in asymptomatic HIV-infected individuals. SETTING: Two specialists HIV/AIDS outpatient facilities in London. PARTICIPANTS: Eighty-four HIV-1 seropositive asymptomatic men; 29 HIV-1 antibody-negative homosexual men at high-risk for HIV infection and 48 HIV-1 antibody-negative men at low-risk for HIV infection as controls. MAIN OUTCOME MEASURES: Single voxel, gradient-localized proton MRS performed at 1.5 T with 135 msec echo-time and 1,600 msec repeat-time in an 8 ml volume of interest positioned in the parieto-occipital white matter. Spectroscopic results were expressed as ratios between the areas under the N-acetyl (NA), creatine (Cr) and choline (Cho) resonance peaks. RESULTS: There were no differences between those controls at high and those at low-risk for HIV infection. Comparing the combined control groups with the asymptomatic seropositive patients there were statistically significant differences in NA/Cho, NA/Cr (both P < 0.05) and NA/(NA + Cho + Cr) (P < 0.01). CONCLUSION: Abnormalities in cerebral biochemistry may be demonstrated by proton MRS during asymptomatic HIV-1 infection.

Brain↗
PubMed1997

Preliminary results on the management of unruptured intracranial aneurysms with magnetic resonance angiography and computed tomographic angiography.

OBJECTIVE: The goal was to assess the capability of magnetic resonance angiography (MRA) and computed tomographic angiography (CTA) to replace catheter angiography in the evaluation of unruptured intracranial aneurysms. METHODS: A prospective evaluation of a 1-year period included all patients suspected of harboring unruptured intracranial aneurysms at a single institution. All patients underwent magnetic resonance imaging, MRA, and CTA, for comparison with intraoperative findings or results from catheter angiography. Both MRA and CTA now provide submillimeter resolution of vascular structures, with accurate detection of intracranial aneurysms of a diameter greater than or equal to 3 mm. This resolution calls into question the universal need for catheter angiography in the care of patients with suspected intracranial aneurysms. When the catheter angiography can be avoided, radiological costs can be reduced by as much as two-thirds while eliminating the risk of arterial injury and stroke. RESULTS: Excellent visualization of the intracranial vasculature was provided by both MRA and CTA. No vascular lesion was detected at surgery or by formal angiography that was not visualized by noninvasive angiographic techniques. The three-dimensional anatomy of the aneurysm complex (unavailable with catheter angiography) was well depicted by both MRA and CTA. CTA was unique in its capacity to display the relationship of vascular structures to bone, information that is invaluable for planning operative strategies for lesions such as carotidophthalmic artery aneurysms. Additionally, acquisition of CTA images was very rapid, with a scanning time of less than 1 minute. Both MRA and CTA allowed for retrospective manipulation of data into an infinite number of views, including views that paralleled those encountered through the operative microscope. Additionally, both MRA and CTA can depict the internal anatomy of aneurysms, an ability not possessed by intra-arterial angiography. This ability alerts the surgeon to possible intraoperative risks, such as plaque in the lumen of an aneurysm or calcium within the walls of the arteries. CONCLUSION: Both MRA and CTA provide several advantages over digital subtraction angiography, in addition to reduced costs and avoidance of arterial injury and stroke. These include retrospective manipulation of data in a 360-degree format, visualization of the internal anatomy of arteries and aneurysms, three-dimensional depiction of anatomy, and rapid data acquisition. Preliminary data and a review of the literature suggest that MRA, when used in concert with CTA, can replace catheter angiography in the assessment of select patients harboring unruptured intracranial aneurysms. Although no firm conclusions or generalizations can be drawn from this small cohort of patients, it is hoped that this report will stimulate interest and further study at other institutions.

Aged↗